Hydrochloric Acid → 1-Benzylazocan-5-one

Participants

Reaction Steps

To a stirred boiling slurry made from potassium (1.28 g, 32.8 mmol) and t-BuOH (2.43 g, 32.8 mmol) in xylene (182.5 mL) under N2 was added diethyl 4,4′-(benzylazanediyl)dibutanoate (O2) (5 g, 14.9 mmol) over 5 hrs in xylene (37.25 mL). The mixture was stirred and heated at reflux for 1 hr. After being cooled, the reaction mixture was neutralized with 6N HCl (100 mL) and then was extracted with 6N HCl (3×50 mL). The combined acid solutions were filtered and the filtrate was heated under reflux for 1 hr. After cooling, the mixture was basified with concentrated KOH solution to pH 10 with cooling and extracted with dichloromethane. The combined organics were dried over Na2SO4 and concentrated to give a residue. Another 17 batches were done in parallel. The combined residue from 18 batches was purified together by column (P.E./EtOAc 5:1) to give 1-benzylazocan-5-one (O3). 1H NMR (CDCl3, 400 MHz) δ 7.30-7.33 (m, 2H), 7.21-7.25 (m, 3H), 3.56 (s, 2H), 2.55 (t, J=6.0, 4H), 2.24 (t, J=6.4 Hz, 4H), 1.86-1.91 (m, 4H).

Provenance & Evidence